Since the appearance of digital video streaming protocols and IP Network cameras around the beginning of the 21st century, video surveillance has been evolving into an all-digital environment of ever-increasing size and complexity.
Whereas the digital video recorders (DVR) of today provide 16, 32 and even 64 channels of recording for analog cameras, the networking of digital IP network cameras and similar devices allows networks of unrestricted size to be set up. The consequence of this is that a vast and distributed body of video data is generated that must be collected, stored, catalogued and managed. A common apparatus for recording such video is the Network Video Recorder (NVR) and a plurality of Network Video Recorders are generally used to create larger systems.
Furthermore, the increased sophistication of these cameras and video devices may result in multiple video streams per device, plus the ability for each device to perform environment and scene analysis and transmit event and status messages to the network. Video analytics, such as recognizing faces, vehicles, license plates and more, provide richer data intelligence than was available before.
Capabilities of network IP cameras have also become more standardized with the emergence of interface protocols such as ONVIF and PSIA. Furthermore, the popularity of video clips used for entertainment and education on sites such as YouTube™ (www.youtube.com) has resulted in a high degree of openness and standardization of technologies, for example, multimedia format HTML5 from the World Wide Web Consortium (W3C) (www.w3.org).
In contrast to entertainment systems, video surveillance systems still tend to be largely proprietary to one vendor or another, and standardization in general has been uneven. There are therefore significant improvements in video quality, flexibility, scalability, reliability, inter-vendor operability and cost-effectiveness to be gained from being able to separately record, process, analyze, store, manage, search and retrieve video-stream (video) and video-event (event) information as well as maintain the relationships between these two kinds of information.
Although the speed of networks is improving year upon year and excellent video compression technology is becoming more widely available, the increasing demand for more cameras and better resolution images is resulting in an overwhelming amount of video data being generated. It is therefore increasingly uneconomical to provide video transmission to a central location and storage for all cameras on a single server. Furthermore, aggregating too much data in a single location also creates a bottleneck when access to the data is required through a bandwidth limited connection, such as a broadband Internet access connection.
Certain prior art solutions are known that address aspect of networking multiples cameras. For example:
US 2009/0295925: for “Network camera management system and network camera management method”, filed on May 14, 2009. This patent application discloses a network camera management system for managing a plurality of cameras connected to a predetermined network.
US 2012/0113265: for “Network video recorder system”, filed: Sep. 30, 2011. This patent application discloses a method for implementing a security system for a set of IP-enabled security devices connected by an Ethernet network to a set of local Ethernet ports on a network video recorder.
U.S. Pat. No. 8,117,252: for “Video-monitor/recording/playback system”, filed: Dec. 24, 2003. The patent discloses a Network Video Server (NVS) that communicates with networked devices and cameras that are physically wired, or wirelessly connected to a network infrastructure (backbone). Video output, recorded output and system control is made available through standard web browser interfaces that can be connected to the local LAN, or on any remote leg of a WAN to which the server is attached.
Additionally, “Web Services Dynamic Discovery” (WS-Discovery) Version 1.1, OASIS Standard, 1 Jul. 2009 discloses a discovery protocol to locate services. In an ad hoc mode of operation, probes are sent to a multicast group, and target services that match return a response directly to the requester. To scale to a large number of endpoints and to extend the reach of the protocol, the protocol defines a managed mode of operation and a multicast suppression behaviour, if a discovery proxy is available on the network. To minimize the need for polling, target services that wish to be discovered send an announcement when they join and leave the network, which may be found at http://docs.oasis-open.orq/ws-dd/discovery/1.1/os/wsdd-discovery-1.1-spec-os.pdf.
A PELCO TECHNICAL WHITE PAPER entitled “Reducing Costs While Enhancing Reliability of Video Surveillance Storage Systems” discloses operation of IP-based physical security platforms including networked video cameras: which may be found at http://www.pelco.com/documents/whitepapers/en/shared/video-storaqe-whitepaper.pdf.
There is therefore a need for new solutions for networking cameras in a way that addresses some of the problems mentioned above.